Locking ring

ABSTRACT

A locking ring for a plastic container for fluids, comprising a U-shaped channel fitting over a rim and a lid of the container, and also comprising a novel guide below a sealing ridge, said locking ring having a pre-installed position on the rim and the lid, and in said pre-installed position said guide being balanced evenly and fitting snugly against an outer portion of the rim of the container, said pre-installed position, and so that the locking ring may be pressed onto the rim and the lid with less force than otherwise.

The field of the invention is air transportation of fluid in cans.

When plastic containers for fluids such as paint cans are shipped by air, they must have a device attached to the lid to prevent the lower atmospheric pressure at high altitude from causing the can to lose its seal on account of the higher pressure of air trapped above the fluid at the top of the inside of the can. That is, these containers are filled in facilities located at altitudes much closer to sea level than the high altitudes in which air cargo travels. When these cans are filled there is a small amount of air trapped between the top of the paint or fluid and lid of the container. For example, at sea level, the atmospheric pressure of the trapped air is approximately 14.7 lbs per square inch, and the air pressure trapped under the lid and the air pressure outside the lid in the environment are roughly equivalent. On the other hand, atmospheric pressure at an altitude of 30,000 feet is approximately 4.4 lbs per square inch so that, when paint is transmitted by air at these higher altitudes, there exists a risk of losing the seal from the much greater pressure of air trapped inside the container. Government regulations and common sense require that containers in this setting be protected from loss of seal by means of a physical device attached to the container. Although rings for mounting on the tops of containers have existed, they have been either ineffective at preventing loss of seal or their configurations have made installation haphazard or unwieldy.

The efficacy and value of the present invention is a function not only of the actual locking means, but also of the utility of applying the ring from the lid and rim of a can.

What is disclosed is an improved locking ring which holds securely and is easier to apply from the container's rim and lid, on account of the unique structures provided. The invention will not only contain the lid and eliminate the potential for the container to burst open but, if the seal between the lid and rim were lost, the invention would also contain the fluid inside the container.

The container to which the locking ring may be applied may be of any shape including, without limitation, a cylinder, a rectangular prism, a substantially rectangular prism (including one which is tapered for nesting when empty), and the locking ring conforms to the shape of the container, as described herein. Herein, the term “ring” can therefore denote any shape which is circular or not circular including, without limitation, rectangular or rectangular with rounded corners.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a top view of one embodiment of the locking ring for a cylindrical container.

FIG. 2 is a section view of one embodiment of the locking ring for a cylindrical container along line 2-2 as indicated in FIG. 1.

FIG. 3 is a section view of a portion of the channel of one embodiment of the locking ring in FIG. 1 at a greater scale.

FIG. 4 is a section view of a portion of the sidewall, lid and rim of a cylindrical container, showing the sidewall, lid and rim and one embodiment of the locking ring in a pre-installed position.

FIG. 5 is a section view of a portion of the sidewall, lid and rim of a cylindrical container, showing the sidewall, lid and rim and one embodiment of the locking ring in an installed position, wherein the trapped air pressure is roughly equivalent to the atmospheric pressure.

FIG. 6 is a section view of a portion of the sidewall, lid and rim of a cylindrical container, showing the sidewall, lid and rim and one embodiment of the locking ring in a installed position, wherein the trapped air pressure inside the closed container is larger than the atmospheric pressure.

The invention comprises a plastic locking ring 1 comprising a channel 2 which is pressed down onto a container so that the rim A and lid B of the container are locked in a closed position. The can and rim are not part of the present invention but are shown for illustrative purposes in U.S. Pat. No. 8,985,383 disclosing a can, and said patent is expressly incorporated in its entirety herein for illustrative purposes regarding an example of a container configuration for which the present invention may be used. The present invention may be used on any other container which has a lip created by an outermost portion D of a rim seated on a can sidewall, wherein the rim's outermost portion D has a diameter (for a cylindrical container) or width (for a non-cylindrical container) which is slightly larger than the diameter or width of the sidewall of the container.

In one embodiment, the present invention comprises a channel 2 comprising, on its top side (which is closest to the arrow pointing from element number 1 on FIG. 2) an inner surface 16, a top surface 17, and an outer surface 18. In this embodiment, the channel 2, a modified U-shaped structure on its bottom side (opposite the arrow from element number 1 in FIG. 2) where the channel contacts a container, comprises elements integral to one another (from innermost to outermost) an inner wall radius 8, an inner wall 3, a first ceiling radius 9, a ceiling 4, a second ceiling radius 10, and an outer wall 5. The channel 2 receives the top outer perimeter of the container which, in one embodiment, is that portion of the container rim A which is seated on the container sidewall C. The rim A, where seated on the sidewall C, creates a lip at the end of the outermost portion D of the rim A which has a slightly larger diameter than the sidewall C. In one embodiment a sealing ridge 6 is integral to the outer wall 5 at a first point 11, and the sealing ridge 6 is snapped by means of pressure into position below the outermost portion D of the rim A of the container, although the specific shapes of the structures may vary from the shapes depicted in the figures. The sealing ridge 6 is integral to a guide 7, and the combination of the guide 7 (beginning at a second point 12) and the sealing ridge 6 which allows the locking ring 1 to be placed into a pre-installed position uniformly and balanced evenly around the rim and lid, as depicted in FIG. 4. In FIG. 4, the locking ring 1 is located optimally on top of the container rim A so that the locking ring 1 may be pressed down into an installed position on the container rim A, as shown in FIG. 5 which is in the installed position. In one embodiment, and in the installed position in FIG. 5, the sealing ridge 6 is contacting the outermost portion D of the rim A, and the apex 13 of the sealing ridge is pressed against the upper portion of the sidewall C. In another embodiment the sealing ridge 6 is positioned just below the outermost portion D of the rim A, although not contacting the outermost portion D of the rim A. The guide 7 enables the locking ring 1 to be placed in and maintained in an optimal pre-installed position which allows the sealing ridge 6 to be distributed evenly around the container rim A, so that less force is required to finish the installation of the locking ring 1 onto the container. That is, prior art locking devices have had no structure which prevents the tilting of the locking ring. If a prior art locking device is tilted unevenly on top of the container rim and lid, then installing the locking device can be impossible even with application of a large amount of force. That is, without the guide 7 the locking ring would be either (1) impossible to install because one side of the sealing ridge 6 cannot be driven downwardly, or (2) difficult to install without damage to the sealing ridge 6, thereby reducing the locking ring's ability to lock the lid down. When the locking ring is in the pre-installed position as shown in FIG. 4, the locking ring may then be pressed onto the container rim A so that, in the installed position, the sealing ridge 6 is underneath the outermost portion of the container rim A and the sealing ridge 6 provides a mechanical barrier to expulsion of the container lid on account of the greater air pressure inside when the can is in an unpressurized cargo compartment at high altitude.

Other embodiments of the invention are optimized for movement by the locking ring during installation and also during the movement of the lid B when the pressure of air trapped inside the container is higher than the atmospheric pressure, as indicated by the arrows pointing upward in FIG. 6, wherein the trapped air pressure is pushing against the inner surface of the lid B. This sometimes referred to herein as a loaded position. Although the trapped air pressure will be uniform, the movement of the lid B will be greater towards the center of the lid B, as shown in FIG. 6, and therefore the movement on the rim A and the locking ring 1 will be rotational rather than linear. That is, the movement of the locking ring will be greater at the inner surface 16 and innermost portion of the top surface 17, as shown in FIG. 6. This rotational deformation will cause the first slope 14 to rotate further towards the outermost portion D of the rim A as shown in FIG. 6, to further anchor the sealing ridge 6 against the sidewall C.

In another embodiment, the channel comprises an inner wall radius 8 which eases installation of the ring. In this embodiment, the inner wall 3 and the ceiling 4 are integral at a first ceiling radius 9. Also, in this embodiment, the ceiling 4 and the outer wall 5 are integral at a second ceiling radius 10. The outer wall 5 is integral to the sealing ridge 6, and the sealing ridge rises in a first slope 14 from a first point 11 to an apex 13, where the sealing ridge 6 descends in a second slope 15 to a second point 12 where the guide 7 is integral to the sealing ridge 6. The shapes and particular structures of the channel are variable, especially to fit the geometry of different containers, as long as there is an outermost portion D of a rim A which has a diameter or width slightly larger than the container's sidewalls.

For a container substantially in the shape of a rectangular prism (including a rectangular prism with rounded corners) and comprising a rim and lid and having a horizontal cross-section (i.e., parallel to the bottom of the container) which is substantially rectangular (including for example a rectangle with rounded corners), in one embodiment the locking ring 1 in one embodiment has a channel similar to that depicted as channel 2 for the cylindrical container and with structures on the bottom side of the channel similar to those shown in FIGS. 3-6 including an inner wall radius 8, an inner wall 3, a first ceiling radius 9, a ceiling 4, a second ceiling radius 10, and an outer wall 5, but in other embodiments the specific shape of the channel may vary. In this embodiment a sealing ridge 6 is integral to the outer wall 5 at a first point 11, and the sealing ridge 6 is snapped by means of pressure into position below the outermost portion D of the rim A of the container. The sealing ridge 6 is integral to a guide 7, and it is the combination of the guide 7 at a second point 12, and the sealing ridge 6 which allows the locking ring 1 to be placed into a pre-installed position uniformly and balanced evenly around the rim and lid, as depicted in FIG. 4, but in the shape of a square, not a circle. The locking ring 1 is located optimally on top of the container rim A so that the locking ring 1 may be pressed down into an installed position on the container rim A, as shown in FIG. 5 which is in the installed position. In the installed position in FIG. 5, the sealing ridge 6 is below the outermost portion D of the rim A, and the apex 13 of the sealing ridge is pressed against the upper portion of the sidewall C. The guide 7 enables the locking ring 1 to be placed in and maintained in an optimal pre-installed position which allows the sealing ridge 6 to be distributed evenly around the container rim A, so that less force is required to finish the installation of the locking ring 1 onto the container.

In one embodiment, the invention is a locking ring for a plastic container for fluid, said locking ring having a shape of a horizontal cross-section of the container, said locking ring comprising a U-shaped channel for receiving a rim and a lid of the container, said U-shaped channel comprising an inner wall and an outer wall, said outer wall being integral to a sealing ridge and said sealing ridge being integral to a guide, so that when the sealing ridge and guide are positioned in a pre-installed position adjacent to the rim then the locking ring may be pressed to an installed position in which the sealing ridge contacts a sidewall of the container and an outermost portion of the rim. The locking ring in an installed position, when atmospheric pressure is less than air pressure inside the container and the lid is forced upward to a loaded position, the sealing ridge presses against the outermost portion of the rim and holds the lid in place. In different embodiments, the shape of the horizontal cross-section (i.e., parallel to the bottom or the top) of the container may be circular, rectangular, rectangular with rounded corners, or any other shape, and so the shape of the locking ring will correspond to the shape of the cross-section of the container. Further, in embodiments in which the container is tapered to allow for nesting of the empty containers, the cross-section of the container to which the shape of the locking ring will correspond will be at the top of the container, that is, the portion of the container on which the rim is located, and which is sized to correspond to the dimensions of the locking ring. 

1. A locking ring for a plastic container for fluid, said locking ring comprising a U-shaped channel fitted for receiving a rim and a lid of a container, said U-shaped channel comprising an inner wall, an inner wall radius and an inner surface and an outer wall and an outer surface, said outer wall being integral to a sealing ridge and said sealing ridge being integral to a guide so that, when and the guide is positioned in a pre-installed position snugly adjacent to an outermost portion of the rim, then the locking ring may be pressed to an installed position in which the sealing ridge contacts a sidewall of the container and the outermost portion of the rim, and the inner wall and the inner wall radius also contact the lid, creating a void between the U-shaped channel and the rim and the lid in the installed position.
 2. The locking ring as in claim 1, wherein when atmospheric pressure is less than air pressure inside the container and the lid is forced upward to a loaded position, the sealing ridge presses against the outermost portion of the rim and the U-shaped channel presses against the lid, and holds the lid in place.
 3. The locking ring as in claim 1, wherein the locking ring is circular.
 4. (canceled)
 5. The locking ring as in claim 1, wherein the locking ring is rectangular with rounded corners.
 6. (canceled)
 7. The locking ring as in claim 1, further comprising a first slope between an apex of the sealing ridge and a first point of the sealing ridge, and the first slope is straight between the first point and the apex. 